Neither the source nor the nature of biophysical stimuli significant to new bone formation have been identified. It is not clear whether viscoelastic properties of muscle or neuromuscular activity provides the proper stimuli for modeling and remodeling of bone. The aim of this study is to determine parameters of level, duration and consistency of stimuli which clinical and experimental evidence suggest are associated with bone formation. An experimental model in which new bone will consistently form has been developed using the rhesus monkey. Altering levels of activity in the experimentally controlled system is designed to narrow the focus to that part of the spectrum of biophysical stimuli which are significant to bone formation.